All Troops and Titans have Ranged and Melee Damage buffs in them. However, they are dormant/ non-viable or at a minimal percentage depending on the unit's attack type:
Thor has both Melee and Range Damage buffs but since he is not a Ranger, the Range boost is dormant or not used. This is the same for Militias, Spearmen, etc.
Grenadiers, on the other hand, do Range attacks, but they still have a very minimal melee damage buff to defer close contact attacks. This works the same with other Range Titans.
It is by design that the dormant boosts still show as buffing during attack start-up. But again, if it is not applicable to the Titan or Troop, the boost won't take effect during the battle.
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